Ein Beitrag zur experimentell gestützten Tragsicherheitsbewertung von Massivbrücken

In September 2000 the DAfStb issued a technical recommendation for the experimental assessment of structural safety and usability of concrete structures. By now, the influence of pavement or floor layers and of other factors on the load carrying capacity is not known exactly. In this thesis, it has been investigated how road pavements, the geometry and bridge caps reduce the actions on concrete bridge structures and how these influences should be taken into account in the experimental evaluation of the bending capacity by an additional test load increment. In co-operation with a local authority in Stralsund, Germany, comprehensive loading test could be performed at an abandoned concrete bridge with prefabricated girders. Between loading cycles, the pavement has been stepwise disassembled. In addition, the ultimate load of the structure as well as of an individual girder has been determined in fracture tests. By means of a hybrid analysis, i.e. a numerical simulation supported by experimental data, the influences of the pavement layers have been determined. These results were verified by experimental observations obtained in past bridge tests. The influence of the pavement layers on the load carrying capacity appeared to be as high as 28% at the maximum for the bridges investigated. Since the loading vehicle BELFA has been completed in March 2001, test loads can be applied now self-securing to bridges in the so-called large load circuit, i.e. the structure is loaded including supports and foundation. The technical concept, the principle and possible applications of the BELFA are described. The results presented will allow to determine the additional test load increment for compensating the influence of pavement layers, structural geometry and bridge caps in future experimental safety evaluations. For this analysis, the exact geometry of the structure, the thickness of the pavement layers as well as their material properties, especially the modulus of elasticity, have to be known. Guidelines for the analysis procedure as well as for simplifying assumptions are given.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Technische Universität Dresden

Year

2003

Author dc:creator

• Gutermann, Marc

Contributors dc:contributor

• Opitz, Heinz
• Stritzke, Jürgen
• Steffens, Klaus

• Belastungsfahrzeug
• Bruchversuch
• Einfluss von Straßenbelag/ Bauwerksgeometrie/ Kappen
• Experimentelle Tragsicherheitsbewertung
• Straßenbrücke
• assessment of structures
• contribution of pavements
• experimental safety evaluation
• fracture test
• loading vehicle
• road bridge